Recently, there is an increasing demand for enlarging a screen of a display device. However, enlarging a screen of a display device suffers many technical limits, and so development of a large display device requires much time.
In order to address the demand for enlarging a screen of a display device, for example, there is an attempt for arranging a plurality of display panels in a tiled pattern (tiling a plurality of display panels) and joining up display screens of the display panels so as to apparently realize a display device with a large screen.
However, a display panel includes a display region constituted by a plurality of pixels and a frame region formed outside the display region. The frame region includes a sealing section for causing a pair of substrates to face each other and sealing and retaining display medium (electric optical element) such as a liquid crystal material between the substrates, a driving circuit mounting section for driving pixels etc., which sections do not contribute to display.
Accordingly, the tiling technique for tiling a plurality of display panels and joining up display screens of the display panels suffers a problem that joint lines between the display panels are seen. Such a problem is common among direct-view display devices such as liquid crystal display devices (LCD), plasma display devices (PDP), and organic electroluminescence (EL) display devices independently of the type of display (display medium).
In order to deal with the problem, recently, there is proposed a display device with a light guide element on a display surface for the purposes of making a frame region of a display panel less apparent and enlarging a display area.
For example, Patent Literature 1 discloses a liquid crystal display device having an optical fiber face plate that covers the whole surface of a display panel. The optical fiber face plate is intended to guide a part of light emitted from a display region to a frame region in order to display an image seamlessly.
Furthermore, Patent Literature 2 discloses a display unit and a multiple-type display, each having an optical fiber face plate complex intended to enlarge and display light emitted from a display region to correspond to the size of a peripheral of the display region, thereby displaying an image seamlessly.
Furthermore, Patent Literature 3 discloses a display device which has optical compensation means constituted by a large number of tilted thin films and transparent mediums filling spaces between the tilted thin films and which guides a part of light emitted from a display region to a frame region via the optical compensation means so as to display an image seamlessly.
Furthermore, Patent Literature 4 discloses a display device in which a diffusing member including a large amount of optical fibers is provided only at a region in the vicinity of a frame region and which guides light emitted from a display region to the frame region via the optical fibers, thereby displaying an image seamlessly.